Setter for timeOfDay

[FMorschel]

This is requesting a way of setting timeOfDay. Either by a setter or a method. I think it should accept something like a Duration and be clear that it would remove any 24h period from it before setting the time.

Today you'd need to: myDateVar.date.add(newTimeOfDay); this is requesting something like myDateVar.timeOfDay = newTimeOfDay; to exist.

I also think this package could have an exactTimeOfDay getter for milliseconds and microseconds as well, this would help with more precise calculations where they are needed (or simply add this info in the current timeOfDay getter).